Working stand of multistrand roller cold-tube and -pipe rolling mill

ABSTRACT

A working stand comprising a casing in which is mounted sets of working tools connected by means of a rigid joint with a slide. The casing and the slide being coupled with a drive through a leverage system effecting a reciprocating motion during which the casing moves with a higher speed and passes a larger path than the slide which results in that forming rollers of the working tool, on rolling over deform (roll down) the tubes or pipes mounted on mandrels. The stand is designed with a view to enhancing the mill production.

United States Patent [1 1 Sherman et al.

[ 1 Dec. 11, 1973 WORKING STAND OF MULTISTRAND ROLLER COLD-TUBE AND -PIPE ROLLING MILL [76] Inventors: Vladimir Efimovich Sherman, ulitsa Vainera, 13a, kv. 14; Georgy Viktorovich Dubonosov, prospekt llicha, 29, kv. 6; Sergei Fedorovich Portnov, ulitsa Vainera, 13a, kv. 85; Jury Alexeevich Fedotov, ulitsa Vainera, 5a, kv. 8; Yakov Zelmanovich Grinberg, ulitsa Volodarskogo, 14, kv. 7; Nikodim Nikiiorovich Soloviev, ulitsa Metallurgov, 12, kv. 4; Viktor Grigorievich Pavlov, ulitsa Lenina, 108, kv. 7; Efim Fedorovich Dmitriev, prospekt llicha, 17, kv. 34, all of Pervouralsk Sverdlovskoi oblasti, U.S.S.R.

[22] Filed: June 15, 1972 [21] Appl. No; 263,287

[52] US. Cl. 72/208, 72/214 [51] Int. Cl B2lb 17/06, B21b 21/00 [58] Field of Search 72/214, 220, 208, 72/209 [56] References Cited UNITED STATES PATENTS 3,670,549 6/1972 Tselikov 72/208 3,611,775 10/1971 Gabel et a1. v 72/193 3,211,027 10/1965 Krause 72/208 Primary ExaminerMilton S. Mehr Attorney-John C. Holman et al.

[57] ABSTRACT A working stand comprising a casing in which is mounted sets of working tools connected by means of a rigid joint with a slide. The casing and the slide being coupled with a drive through a leverage system effecting a reciprocating motion during which the casing moves with a higher speed and passes a larger path than the slide which results in that forming rollers of the working tool, on rolling over deform (roll down) the tubes or pipes mounted on mandrels.

The stand is designed with a view to enhancing the mill production.

3 Claims, 7 Drawing Figures PATENIEDUECH ms SHEET 2 [1F 4 PATENIEDHEB 11 m; 3,777,534

SHEET 3 BF 4 IIIIIIIA 1 WORKING STAND or MULTISTRAND ROLLER COLD-TUBE AND rrrn ROLLING MILL FIELD OF THE INVENTION The present invention relates to tube and' p'ipe'prm duction and more particularly to roller cold-tube andpipe rolling mills referred to hereinaftenas roller coldtitbe rolling mills.

BACKGROUND OFTI-I E INVENTION In the present state ofthe art; the cold rollingof tubes or'p'ipes by rollers is effectedin industry only on single strand mills.

Adisadvantage of such single strand mills lies in their low production rate as comparedto other pipe and tubemills.

Being superior to other pipe and tube mills in the quality of their products and "making it possibletoroll tubes and pipes with a diameter to wall thickness ratio of over I00, featuring very good dimensionalaccuracy and surface finish, the roller col d-tuberolling rnills havea low production capacity which is'attributable to anurnber of technological and design factors.

Among the reasons restricting the production of the known roller cold-tube rolling mills are the following:

- inability to further increase the rolling speedithe number of double strokes of a stand perminute) deformation focus) owing to inadequate durability of a working tooland because the ends of the tube (or pipe) being rolled run into those of a pushing tube (or pipe).

The development of rnultistrand roller cold-tube rolling mills holds promise for increasedproduction rates.

The major deterrent to the development of a multistrand roller cold-tube rolling mill is the lack of a functionally dependable working stand adapted for such a mill.

. Attempts have been made to devise a stand for the multistrand roller cold-tube rolling mills. Thus, known in the art is a working stand of a multistrand roller coldtube rolling mill comprising a casing in which are mounted the sets of working tools incorporating supports with specially shaped surfaces over which move (roll over) rollers enclosed in a cage reciprocating with the aid of a leverage system operated from a drive means, the rollers being adapted to deform the tube being rolled which is placed on a mandrel (seeAuthors Certificate of the USSR No. 159784).

The known working stand of the multistrand roller cold-tube rolling mill is provided with the thick-walled casing with ports in which areset up the supporting planks. The working rollers which perform plastic deformation on the tube being rolled are mounted in the cages. Each cage connected by means of two rods with the leverage system actuated by the drive means performs a reciprocating motion. The rollers set up in the cage move between the supporting planks and the tube being rolled rolling down the latter.

Inherent in the conventional working stand of the multistrand roller cold-tube rolling mill are the following disadvantages:

- complicated mill adjustment owing to the fact that each cage is coupled directly with the leverage system which maylead to cage skewing and inconsistent operation;

- exceptionally complicated replacement of the working tool the supporting planksand rollers insofar as the casing of the working standis made in the form ofa solid thick-walled workpiece which does not provide free access to working stand assemblies in mounting and stripping the working tools.

Owing to the above disadvantages the described hereinbefore working stand has not found use in indus trial application.

SUMMARY OF THE INVENTION The basic object of the invention is to provide a working stand ofa roller cold-tube rolling mill which would offer a substantial increase in the mill production.

Another object of the invention is to provide a working stand of a roller cold-tube rolling mill which would enable the production of tubes featuring high geometric dimensional accuracy along with high-quality surface finish.

These and other objects are attained in a working stand of a multistrand roller cold-tube rolling mill comprising acasing in which are mounted sets of working tolls which incorporate supporting planks with shaped surfaces over which move (roll over) rollers enclosed in a cage which reciprocates with the aid of a leverage system operated from a drive means, the rollers being adapted to deform the tube being rolled which is placed on a mandrel. In accordance with the invention the working stand is fitted with a guide slide, referred to hereinafter as a slide, arranged between the cages and connected with these by means of a rigid joint through which slide, reciprocating motion is transmitted from the leverage system to the cages.

The slide is preferably provided with a guide rod which will diminish the possibility of cage skewing and wear and will provide for smooth operation of the stand.

It is also sound practice to make the casing of the working stand of split construction built-up of separate casing members connected, on being assembled, with one another by means of a rigid joint and accomodating separate sets of the working tools and the guide rod forming thereby separate stand sections. This will ensure free access to the working tool during repair work and replacement and reduces the stand weight.

The present invention resulted in developing a workingstand of a multistrand roller cold-tube rolling mill which affords a substantial increase in the mill production rate owing to the concurrent rolling of tubes in two and more strands.

The nature of the present invention will be more fully apparent from the following description of an exemplary embodiment thereof to be taken in conjunction with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a schematic side elevational view ofa roller cold-tube rolling mill with a stand conforming to the invention;

FIG. 2 is a a top view of FIG. I;

FIG. 3 is an enlarged longitudinal section of the movable portion of a working stand conforming to the invention at the right-hand portion of FIG. 1;

FIG. 4 is a section on line IVIV of FIG. 3;

FIG. 5 is an end elevational view along arrow A on the movable portion of the working stand presented in FIG. 3;

FIG. 6 is a further enlarged view showing the deformation focus of a tube being rolled in the working stand; and

FIG. 7 is a section on line VIII-VIII of FIG. 6.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, a multistrand roller coldtube-rolling mill comprises a working stand 1 in which the tube a being rolled is subjected to deformation. A movable casing 2 of the stand 1 is coupled through a crankgear 3 with a reducer 4 which is rotated by a drive 8 through a V-belt drive 6 and pulleys 5 and 7.

Member 9 of the mill mounts its elements and gears, which ensure the feeding of tubes 10a to a deformation focus (as shown in FIGS. 6 and 7), their turning as well as retention of the tubes 10 and pivots 11 together with mandrels 12 secured to the pivots 11. The reducer 4 is connected with a tube feeding and turning gear 14 by means of a transmission shaft 13.

The tube feeding and turning gear 14 and the movable casing 2 of the stand I operate synchronously. In operation, the movable stand casing 2 reciprocates being set in motion by the reducer 4 through the crankgear 3. The gear 14 converts the continuous rotary motion transmitted from the same reducer 4 by the transmission shaft 13 into intermittent rotation. The latter is transmitted by the gear 14 with the aid ofa shaft 15 and a screw 16 to its actuating members a pivot chuck 17 and a tube feeding and turning chuck 18 which serve to feed the tubes and to turn both the tubes and the pivots 11. The tubes are fed and turned when the movable stand casing 2 approaches its extreme position.

The tube turning shaft 15 and the tube feeding screw 16 are issued from the tube feeding and turning gear 14. The first one is coupled with locks 19 of the chuck 17 for clamping the pivots 11 and with the tube feeding and turning chuck 18 which results in the concurrent turning through one and the same angle of: the pivots 11, mandel attachments and the tubes 10 being rolled and clamped in the tube feeding and turning chuck 18.

The feeding screw 16 is connected with the tube feeding and turning chuck 18 by means of a sliding nut (not shown in the drawings). Therefore as the tube feeding screw 16 turns through a certain angle, the chuck 18 advances for a feed pitch. The tubes are fed and turned simultaneously. To support the tubes being rolled and the pivots; the housing is fitted with collarplate supports 20.

The mill functions in the following manner. First the mill is reloaded. To do that, pivot clamping locks 19 are unlocked and the tubes 10 being rolled is placed on each pivot. Illustrated in FIGS 1 and 2 is a double strand mill comprising accordingly two chucks 18, two pivots 11, etc. As soon as the tubes being rolled are placed on the pivots, the locks 19 for clamping the pivots 11 are locked keeping the pivots from being traversed axially. Next the tubes 10 being rolled are advanced through collar-plate supports 20 along the pivots until they strike against unfinished tubes 10 a remaining after the preceding cycle. After that the tubes being rolled are clamped in the tube feeding and turning chuck 18, the mill is ready for the next working cycle. Then the drive unit 8 is activated and imparts rotation through the V-belt drive 6 to the step--down reducer 4, from which the motion is transmitted to two mill systems: the tube feeding and turning gear 14 and movable stand casing 2. In the tube feeding and turning gear 14, the continuous rotary motion of transmission shaft 13 is converted into an intermittent rotary motion transmitted to a tube turning shaft 15 and tube feeding screw 16. Conversion of the continuous rotation into the intermittent one is effected at the strictly present moment when the movable casing 2 of working stand 1 is in its extreme position during reciprocation. In modern roller cold-tube rolling mills, the conversion is performed by means of a Maltese cross geneva feed (not shown in the drawing) which is a major unit of the tube feeding and turning gear 14. Issuing from the above gear 14 is the tube feeding screw 16 which upon being turned through a certain angle with the aid of a sliding nut (not shown in the drawing) engaged with the screw and arranged in the tube feeding and turning chuck 18 advances the chuck for a feed pitch whereas the tube turning shaft 15 on being turned simultaneously with the tube feeding screw 16 revolves the tubes and pivots 11 clamped in the chuck 18 through the same angle. Hence, the operation of the tube feeding and turning gear 14 and its working elements 17, 15, 16, 18 and 19 results in the feeding of the tubes being rolled to the deformation focus, their turning (turning over) after each double stroke of the movable stand casing 2 and in the turning of the pivots 11 concurrently with the tube.

Deformation of the tubes is effected in the movable portion of the stand (FIGS. 3 through 5) to which is imparted a reciprocating motion by the crankgear 3 through the movable stand casing 2.

The working stand of the multistrand roller cold-tube rolling mill comprises a stationary housing 21 (FIGS. 1 and 2) to which is fastened guide runners 22. The movable portion of the working stand together with its movable casing 2 reciprocates along the runners 22 on rollers 23. The movable casing 2 of the working stand is articulated with a leverage system 24 (FIG. 4) secured on a support 25 (FIGS. 4 and 5 which is mounted on the housing 21. The movable casing 2 of the working stand consists of separate casings 27 interconnected by means of rigid joints by a frame (FIGS. 3,5) and accommodating cages 28 with working rollers 29. Secured in the casings 27 are working supporting planks 30 (FIG. 5) over which during the rolling procedure move (roll over) working rollers 29 mounted in the cages 28, the roller trunnions being arranged in Texlolite bushes 31. The cages 28 are rigidly fixed in a slide 32 (FIGS 3, 5) articulated by means of a strap 33 and hinges 34 and 35 to a link 36 of the leverage system 24. Meanwhile, the link 36 is articulated by means of a rod 37 with the frame 26 of the movable stand casing 2. The slide 32 is provided with a guide 38 located in a casing 39 and connected with the slide 32 by means of a rigid joint. The tubes are rolled on reciprocation of the movable casing 2 of the stand I of the roller coldtube rolling mill. The casings 27 and 39 securely connected by the common frame 26 move at a higher speed and pass a larger path than the slide 32 and connected with it by means of rigid joints cages 28 with the working rollers 29. This is attributable to the fact that a hinge 40 which serves to attach the leverage system 24 to a hinge 41 of the frame 26 (FIG. 3) is separated a greater distance from the support 25 than the hinge 36 by means of which the slide 32 is attached to the link 36 with the aid of the strap 33.

On account of a difference in the rates of movement and the paths of the casings 27 and 39, on the one hand, and the cages 28, on the other hand, the slide 32 together with the cages 28 connected to it by means of a rigid, joint and provided with the working rollers 29 and the guide 38, traverse with respect to the casings 27 and 39, the working rollers 29 being rolled over the supporting planks 30 secured in the casing 27. The magnitude of this mutual traverse can be adjusted by manipulating the hinge 35, i.e. by drawing it nearer or farther from the support 25.

The cages 28 being rigidly fixed in the slide 32 and the guide 38 being connected to the slide 32 also by means of a rigid joint, all the system articulated with the aid of the hinges 34 and 35 and by the strap 33 with the link 36 will be adjusted by traversing the link 36. The tubes being fed and concurrently turned by the tube feeding and turning chuck 18 are rolled down in the deformation focus (FIGS. 6 and 7) to the present wall thickness and diameter. Each casing 27 of the stand accommodates the set of the working tools. The supporting plank 30 secured in the casing 27 traversing with a higher speed than centerpoint 0. (FIG. 6) of the roller 29 mounted in the cage 28 causes the trunnions of the roller 29 to roll over the shaped surface of the plank 30, the roller working part being used to roll down the tube on a mandrel 12. During each double stroke of the stand the metal stock fed to the deformation focus will be rolled down.

What is claimed is: i

l. A working stand for a multistrand roller cold-tube and -pipe rolling mill comprises, in combination: a casing; sets of working tools mounted. in said casing; said sets of the working tools incorporating supporting planks with shaped surfaces and cages with rollers in them; a slide in which are rigidly fixed said cages; a leverage system connected through a crankgear with drive means and with said slide and casing for effecting a reciprocating motion during which said casing moves at a higher speed and passes a larger path than said slide coupled to it by means of a rigid joint said cages with working rollers resulting in that said slide and said cages with the working rollers connected to the slide by means of a rigid joint traverse with respect to said casing, said rollers including trunions rolling over the supporting planks and their working sections for deforming (rolling down) the tube orpipe to be rolled placed on a mandrel.

2. A working stand of claim l in which said slide is fitted with a guide for reducing potential skewing of said cages and their wear and results in smooth operation of the stand.

3. A working stand of claim 1 in which said casing is of split construction comprising built-up of separate casing which are interconnected by a rigid joint by a frame and which incorporate said separate sets of working tools and a guide forming separate sections of said stand for affording free access to said working tools during repair and replacement and offers a reduction in the weight of said stand. 

1. A working stand for a multistrand roller cold-tube and -pipe rolling mill comprises, in combination: a casing; sets of working tools mounted in said casing; said sets of the working tools incorporating supporting planks with shaped surfaces and cages with rollers in them; a slide in which are rigidly fixed said cages; a leverage system connected through a crankgear with drive means and with said slide and casing for effecting a reciprocating motion during which said casing moves at a higher speed and passes a larger path than said slide coupled to it by means of a rigid joint said cages with working rollers resulting in that said slide and said cages with the working rollers connected to the slide by means of a rigid joint traverse with respect to said casing, said rollers including trunions rolling over the supporting planks and their working sections for deforming (rolling down) the tube or pipe to be rolled placed on a mandrel.
 2. A working stand of claim 1 in which said slide is fitted with a guide for reducing potential skewing of said cages and their wear and results in smooth operation of the stand.
 3. A working stand of claim 1 in which said casing is of split construction comprising built-up of separate casing which are interconnected by a rigid joint by a frame and which incorporate said separate sets of working tools and a guide forming separate sections of said stand for affording free access to said working tools during repair and replacement and offers a reduction in the weight of said stand. 